Please excuse the long post, I just want to make sure I am clear on my questions.

I made the classic mistakes of 1) an impulse buy, and 2) trusting the pet store guy. The snake is a pet for my son (6 years old) who has asthma, which rules out the normal furry pets. Since this pet store specializes in reptiles, I thought they would know how to properly set up an enclosure. My room mate in college had a Ball Python, and I handled it often, which is why I considered this a good option.

So what I was sold was:
1 - 30 Gal Breeder (36" wide, 18" deep, 12" high) with screen top
1 - Reflector Light, with a 100 Watt Red basking bulb
1 - Hide Box
1 - Water bowl
1 - Bag Substrate (some type of shredded wood shavings)
1 - Very friendly young Ball Python - approx 12" - 18" long

My instructions from the pet store were:
1) Put the light on top of the screen at one end, leave it on 24/7.
2) Put the water dish at the opposite end
3) Put the hide box on the warm end (under the light)
4) Leave the screen open

I keep my house between 74 and 78 year round, so I am more conserned with overheating then underheating. I bought a thermometer from another pet store, to check how things were doing. It is a mechanical gauge type thermometer, which I since learned is not very accurate.

Issues:
1) I checked the temp (with the crappy thermometer) and it read 100 at the warm end and 76 at the cool end.
2) It seems like the light is too bright, being on all the time, and it looks like day all the time
3) I read that you should at least partially cover the top, to keep the heat and humidity in, but also you need to provide adequate ventillation. I tried covering the middle third of the top with aluminum foil, but the temp on the warm end went up to 105 (again on the crappy thermometer), so I removed it.
4) I have read you should have at least 2 hides.
5) I have also read that you should use one (or multiple) under tank heaters UTH.
6) I have read that you should use a ceramic heat emitter CHE

Questions:
So my basic question is: What is the best setup for my cage / room temp / snake??? Please keep recommendations to reasonable cost, at the same time, I want to buy the right equipment once, so that I get this straightened out.
1) Do I need to use UTH's, if so, how many / what size / placed where??? It looks like there is room for at least 2 or 3 medium sized UTHs (Zoo Med Medium OK?) Should I put some or all on a rheostat / thermostat?? Is the Zoo Med rheostat or thermostat OK?? Should they be adjusted so one is on high (warm end) and the other is turned down (cool end)??
2) Should I switch the light out for a CHE?? If so what wattage / placed where / rheostat or thermostat again??
3) Should I cover part or all of the cage?? Plexiglass?? How much ventilation space??
4) Where should I place hides (and how many?) and water dish??

Anything else I should be doing???

Thanks in advance.

Craig